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arXiv · 1510.03842

Nambu--Jona-Lasinio Model Revisited with a Simple Regularization-Renormalization Method

Guang-jiong Ni·Ji-Feng Yang·Jianjun Xu·Senyue Lou
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Abstract

According to the pioneering model proposed by Nambu and Jona-Lasinio (NJL) \cite{2,3}, a massless fermion acquires its mass via a vacuum phase transition (VPT) process. Our discussion is considerably simplified because an effective Hamiltonian for VPT is proposed and a simple regularization-renormalization method (RRM) is adopted. An unambiguous constraint is found as $\frac{π^2}{GΔ^2_1}=\frac{2}{3}$, where $G$ is the coupling constant first introduced in the NJL model while $Δ_1$ the mass of fermion ($f$) created after the VPT. The masses of bosons with spin-parity $J^P=0^+, 0^-,1^+$ and $1^-$ as collective modes composed of fermion-antifermion pairs ($f\bar{f}$s) are also calculated by the method of random phase approximation (RPA).

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Guang-jiong Ni, Ji-Feng Yang, Jianjun Xu, Senyue Lou. 2015-10-13. Nambu--Jona-Lasinio Model Revisited with a Simple Regularization-Renormalization Method. https://arxiv.org/abs/1510.03842

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